Dowel bar adjusting and aligning device



April 28, l953 J. N. HEL'rzEL 2,636,426

nowEL BAR ADJUSTING AND ALIGNxNG DEVICE Filed Sept. 18, 1946 @gz 3f Mmmm W am A ATTORN .YS

Patented Apr. 28, 1953 DOWEL BAR ADJUSTING AND ALIGNING DEVICE John N. Heltzel, Warren, Ohio; The Union Savings & Trust Company of Warren, Ohio, and Carl J. Heltzel, executors of said John N. Heltzel, deceased Application September 18, 1946, Serial No. 697,699 4 claims. (01; 94-51) The present invention relates to improvements in dowel bar adjusting and aligning devices and more particularly refers to adjusting and aligning devices for use in connection with the dowel bars and dowel sockets and/or dowel bar bearing elements for load transfer devices currently employed in connection with concrete constructions, such as airportv runways, concrete roads and the like in which individual slabs of concrete are individually poured and laid with dowel bars' tying adjacent slabs together in an -unitary construction which nevertheless admits of local expansion and contraction of the individual slabs. In actual practice, unless the dowel bars, sockets or bearings are installed with their axes in exact parallelism it is difficult to withdraw the bulkheads or side forms because the openings in" such bulkheads will jam against bent, misaligned or distorted dowelA bars in the process of the bulkheads being slid longitudinally of the dowel bars in disassembling the bulkhead from the dowel bars after the initial slab has been poured and hardened.

At the same time, such dowel bars must be in exact alignment with the plane of the finished surface of the roadway; otherwise contracting and expanding movement of one slab relatively to the other will require that one slab ride upwardly thus causing surface disalignment at the joint and rapid deterioration of the concrete edge due to tramo movement over the same.

The failure of dowel bars in the respects above noted has been caused by misalignment of the bars during the pouring of the concrete, which renders the dowel bars ineffective and detrimental to the roadway to such an extent that many highway engineers are opposed to the use of dowel bars regardless of the apparent necessity of their use in order to maintain the slabs in surface alignment.

With the foregoing and other objects in View, the invention will be more fully described hereinafter and more particularly pointed out in the appended claims.

In the drawings, in which like parts are denoted by the same reference characters throughout the several views,

Figure l is a perspective View of a conventional side form showing an improved dowel bar adjustment and alignment device in place as constructed in accordance with the present invention.

VFigure 2 is a vertical cross-section taken on the lines 2 2 in Figure 3.

' Figure 3 is a fragmentary longitudinal section taken on the. lines 3.3 in Figure 2.

Figure 4 is a horizontal section taken on the lines 6 4 of Figure 2.

Referring more particularly to the drawings the invention is shown as used in connection with a type of bulkhead which is embodied in a standard road form composed of the usual vertical web II, base I2, top rail I3 and upstanding base flange I4.

Such bulkheads or side forms have usually been provided with a series of openings I5 through the web II to receive the dowel bars I6 which are to extend into adjacent slabs of the completed concrete construction.

In accordance with the present invention I propose to depart from standard practice by appreciably and substantially enlarging the diameters of the openings I5 over the external diameters of the dowel bars I6 to allow for ample pl'ay and clearance of the central portions of the dowel bars which octupy such openings I5 to the end that such dowel bars may be adjusted therein in a universal manner, that is in all angular directions of tilting movement about the central portions of the dowel bars and also to permit the dowel bars a limited movement of translation up and down and to the sides horizontally in a universal manner to the end that such dowel bars may be brought to a correctly aligned position where the axes of all of the dowel bars of a single bulkhead or side form may be in true and exact parallelism and whereby the axes of the dowel bars may all be precisely parallel to the plane in which the surfaces of the slabs lie. Furthermore the enlarged openings I5 will permit of easier disassembly and removal of the bulkhead from the dowel bars after one slab has been poured and finished as indicated in Figure 1; the enlarged openings I5 affording greater clearance whereby the walls of the openings I5 will not readily jam against any of the free ends of the dowel bars I6 which. project from the finished slab and over which the bulkhead or side form must be slid in the act of removal of such bulkhead or side form from the slab; inasmuch as such free ends of the dowel bars I6 may become` the base I2 of the side form. The lower end portion of the support 22 acts as one member of a clamp, the other clamp member being formed by the lower inwardly oiset section 26 of a plate having an upper section 25 Which is in substantial vertical alignment with the flange i4 and which fits against the inner face of the support 22. An oiset shoulder 21 connects the two sections 25 and 26.

The support 22 and plate section 25 may be frictionally tightly gripped together upon the bulkhead iianges I2 or I4 by the use of a clamp operating device of any suitable form. In the drawings a clamp bolt or shaft 30 passes rotatably through the support 22 and upper plate section 25 and may be rotated by means of a handle or crank 28. A boss 32 on the bolt 38 engages the outer face of the support 22 while a nut 3l threaded on the inner end of the bolt 30 is tightened by the rotary action of the bolt in one direction against the upper plate section 25. In other words, when the crank 28 is rotated in one direction the nut 3l will be advanced outwardly toward the boss 32 in order to bind the plates together in clamping relation; While reverse rotation of the bolt 3Q will cause the nut 3| to move outwardly from the boss 32 thus relaxing the clamp and thus permitting the support 22 to be slid to a new position longitudinally along the bulkhead iiange I4 or removed when desired. The nut 3l will have to be held stationary by hand or by a wrench or other tool.

Carried adjustably upon the upper portion off the support 22 is` an adjusting plate I8 having an opening 39 therein of the approximate diameter of the external diameter of the dowel bar IB in older to rather snugly receive the free end prtion of such dowel bar to compel this end portion of, the dowel bar to follow the movements of the plate l8- SuchV plate I8 may also be formed with an upper outwardly projecting lip or flange 40 to oier engagement to the iingers to facilitate the lifting of the plate I8 relatively to the support 22 on which such` adjusting plate I8 is carried.

Back of the adjusting plate Illl the support is formed with a slot 33 through which the dowel I also projects. The slot 33 is elongated in a vertical direction or in a direction of adjustment of the plate [8 on the support 22 thus permittingA the end of the dowel bar I8 to move up and Clown in its slot 33 in obedience to the adjustment, imposed upon it bythe adjusting plate I8. This slot 33 will also be of suihcient width to accommodate the dowel bar I6 and also certain other accessories which may or may not be used in connection with the adjusting device.

Also the slot 33 may be extended up sufliciently far to receive therethrough the bolt or shaft il of a clamping device adapted to retain thev clamping plate I8 in adjusted position. This bolt` 4I is threaded upon its inner end portion to receive thereon a travelling nut 38 which may take directly against a backing plate 3l adapted to bridge the upper portion of the slot 33, at the inner side of the support 22. A boss 35 on the bolt 4I is of suiiicient diameter to bridge the width of the vertically elongated slot 36 which may be provided in the adjustment plate I8 for the passage of the bolt 4l. The bolt 4I may be rotated conveniently by the use of a handler or crank Sli.. lf desired a, round openingmay be used in place of the slot; 36, such round opening being only suiiicientv in diameter to encompass the Clamp bolt. M., In other words it mayI not in 4 all cases be necessary to provide both slots 36 and 33 in the vicinity of the clamp bolt 4I. One such slot will be sufficient for permitting of the raising and lowering adjusting movement of the clamp plate I 8.

As a further feature of the invention which may or may not be used in connection with the adjusting device, a reducer plug 2I is adapted to iit removably in each enlarged opening I5 and to have an opening therethrough for freely slidably receiving the dowel bars I6. A lip 20 outstanding from the inner portion of the plug is of suiiicient diameter to engage the inside face of the web Ii of the bulkhead in order to limit the axial movement of the plug 2I and to prevent the plus 2l from being pushed through the opening I5. The external diameter of the plug 2I will preferably be somewhat less than the internal diameter of the opening I5 into which it. lits in order to permit the plug to have a limited rocking movement in the opening I5 as a fuicrum for the dowel bar I5 in the act of rais ing and lowering or moving the dowel bar side to side in the act of adjusting the same, and the lip 2u will cutstand in such relative position as to permitof its limited rocking movement; or the plug might lit snugly in the opening I5 and sufeient clearance providedI between the internal opening of the plug and the dowel bar IS too allow of this-adjusting movement of the dowel A preferably rigid connection i9 may be made between the plug 2i and the adjusting plate I8; this rigid connection being; in the form of an angle iron, a tube or the like; such connection I9 communicating thrust from the plate I8 to the plug 2t for the purpose of pushing the plug into the opening I5 from an operators position at the adjusting device.

It will be seen particularly from Figure 3 that, the slot 33 will have suicient horizontal width not only to clear the side edges oi the connection I 9. but also to admit the lip 20. although the width of slot 33 may be slightly less than the external diameter of the lip 20 inasmuch as such lip. may be rocked through the slot 33 in the act of assembling the device to the bulkhead or road form.

In the use of theV device the support 22; and its clamp are assembled tothe ilange I4 or base lf2 of the side form as shown and inasmuch as the `adjusting plate i8 isv carried. by the support 22 any longitudinal motion of the. support 22 along; the flange le will communicate a, movement, in a horizontal direction to the dowel bar IE. thus causing the dowel bar to`V be, brought to a correct axial position in parallelism with the. axes of all other dowel bars of the side, form or in other words tol bring its. axis into a position at right angles to the vertical plane of the, web il when so desired. After this horizontal. adjustment. has been eiected the lower clamp is tightened to hold the support 22 directly in place while the, upper clamp is relaxed to permit the adjusting plate I8. to; be easily raised or lowered carrying the dowel bar It therewith so as. to accurately adjust the dowel bar in a vertical sense tov a pos-iltion with itsr axis. exactly parallel with a plane passingl through the surfaces. of the. slabs. After adjustment both clamps are tightened to main,- tainy the dowel bar It rigidly inthe adjustedposi` tion during the pouring, vibrating and surfacing ofv the.y concrete at: the oppositeside of the bulkhead or side form.

Where the, reducer plug is, used, the; same is carried through the, connection lzS by the plate- I8 so that such connection I9 and reducer plug;

2l participate in the movements of the plate. I8 although the plug. 2! acts as a shifting fulcrum about which such adjusting movement may be achieved as well as the adjusting movement of the plate 22 .in horizontal directions. However, the reducer plug takes up the additional clear.- ance space of the opening I5 during the assembling and pouring operations and provides support for the dowel bar I6 during such assembling and pouring operations.

It will be understood that a number of adjusting devices will be provided in proportion to the number of dowel bars associated with any particular bulkhead or side form and that such adjusting devices may all be independent structurally and operatively of one another or the same may be connected together for simultaneous adjustment, as indicated by longitudinal aligning member, being adjustably supported at its ends by securing to adjusting plate I8 thereby intermediate dowels are simultaneously adjusted, Will be more fully described in later applic-ation.

After the slab 42 has set as it is desired to remove the bulkhead or side form therefrom, the adjusting device is rst removed by relaxing the clamp 2S to a Ipoint where the inner member of the clamp 26 may be rotated upwardly about the clamp bolt 30 as a center to a position where the plate section 26 will clear the bulkhead flange Iii whereupon the entire device, including the rigid connection I9 and the reducer plug 2I, may be withdrawn axially over the dowel bar I6 which then leaves free all of the dowel bars and the enlarged openings I5 whereby the bulkhead or side form may then readily be slid over the dowel bars and removed from the same and from the concrete. The bulkheads and side forms and the adjusting devices may then be removed to a new site for further paving operations.

The reducer plug 2l may be urged into position by the tubular member IS so that when clamped in position the instrumentalities cooperating for the lpurpose intended will force the reducer plug against the form and prevent its being disengaged therefrom during the placing and finishing of the concrete. However such reducer plug is very readily removed after its purpose has been served.

It will be understood that the adjusting device receives and supports the dowel bar during the placing and surfacing of the concrete.

One means for adjusting simultaneously all the dowel bars o1" a given bulkhead or side form is shown in Figure l in which two adjusting devices of the character previously described are mounted on the side form and associated with the end dowel bars. rlhe intermediate dowel bars have each a perforated intermediate plate I5 4associated therewith in which the perforated plate ts rather snugly over the exposed end of the dowel bar. A longitudinal supporting bar 4t is affixed to all of the perforated intermediate plates 45 and the two vertically adjustable plates I8 of the two end adjusting devices. In this way all of the dowel bars are tied together for simultaneous horizontal and vertical adjustment. If desired, plugs similar to plug 2 I may be mounted in the intermediate openings I5.

In addition, in Figure 1 I have illustrated a socket IGA with a bearing member IEB constituting a load transfer unit, which members may be separate or integral and staked or otherwise erected on the subgrade. The reason for this arrangement is that it is apparent on some types 6? of structure .it .might be thefdesire of the `engineer'to spot the socket, accommodating the dowel bars to be inserted later.. In that case dowel bars are removed from the socket after the bearing members on load transfer elements have been spotted.

While I have disclosed herein but one form of the-invention, other -forms are known to me at the present time and are beingL manufactured. Other applications are in process. I desire it to be understood that I reserve the right `to make changes and modications in thev herein described embodiment of the invention provided such changes lfall within the scope of the appended claims.

What I claim is:

1. In combination, a road form having a web and a base flange, said web having openings therethrough, dowel bars extending through said openings, the diameters of said openings being materially in excess of the external diameters of said dowe1 bars, supports carried by sai-d base iiange and adjustable longitudinally of said road form, clamps for clamping said supports to said road form in adjusted position, reducer plugs tted over the dowel bars and into the enlarged openings in said web, vertical adjusting means carried by said longitudinally adjustable supports and having openings therethrough to snugly receive said dowe1 bars, and connections between. said vertical adjusting means and said reducer plugs for maintaining the reducer plugs in theroad form opening.

2. In combination with a road form having an opening therethrough to receive a dowel bar, said opening being materially in excess of the diameter of a dowel bar, a dowel bar adjusting and aligning ydevice comprising a reducer plug of less diameter than said opening and received within said opening between the'dowel bar and said road form, a support, detachable connecting means connecting said support to said road form for selective attachment along said road form, said support having an opening therethrough to receive a dowel bar, and a plate having means adapted to support the outer portion of a dowel bar and adjustably mounted for vertical adjustment on said support, whereby said plate requires the dowel bar to be adjusted with it vertically relatively to said support and horizontally when the plate and support are together adjusted along the road form.

3. A dowel bar adjusting and aligning device comprising a reducer plug adapted to t within an opening within the web of a road form and to receive a dowe1 bar, a vertically adjustable member, means connecting the reducer plug to said member in spaced relationship, a support, detachable clamping means on said support for selective attachment along said road form and means for adjustably mounting the member on said support, whereby the reducer plug is movable vertically and horizontally of the road form.

4. In combination, a road form having a web and a base ange, said web having an opening therethrough for` receiving a dowel bar, the diameter of said opening being materially in excess of the external diameter of a dowel bar, supporting means carried by said base ange, detachable means connecting said supporting means to said base ange for selective attachment along said base ange, a reducer plug adapted to fit over a dowe1 bar and fitting into the enlarged opening in said web, a member adjustable vertically on said supporting means and having an opening there- JOHN N. HELTZEL.

Referenbes cited m the me of this patent UNITED STATES PATENTS Number Name Date Straub Nov. 6I 1917 Number Name. Date Miller June 17, 1930 Coons et al. Nov. 4, 1930 Geyer Oct. 5, 1937 Nelson July 26, 1938 Isett Aug. 23, 1938 Glson NOV. 12, 1940 

